If you want to cross Cho la pass, you have no other choice but to walk over the glacier Ngozumba to Dragnang (4 679 m asl). Certainly do not stick to the printed map, because the way constantly changes thanks to the movement of the glacier. Ask for sure already at the lodge in Gokyo, where the starting point to the glacier currently is. The path is sometimes marked by stone cairns. And consider also the fact that you can lose your way easily in bad weather.